Astronomy (Meteoroids, Meteors, and Meteorites)

Meteoroids

Particles in space capable of becoming meteors.

• Comet Dust.

• Asteroid Fragments.

• Planetary Impact Ejects.

• The Zodiacal light illustrates the abundance of meteorite material still in the plane of the ecliptic today.

Meteors

The fiery phenomena observed when a meteoroid particle enters the atmosphere.

• Most burn up in the ionosphere.

• About 100 tons enter the atmosphere daily.

• On any night, one can see up to 10 meteors per hour.

Most meteors burn up…

Burn up in the ionosphere.

About _ tons enter the atmosphere daily (meteors)

100 tons.

On any night, one can see up to _ meteors per hour.

10 meteors per hour.

Meteorites

Fragments found to hit the ground following a meteror.

• Stony - The most common, 94%.

• Iron - The most easily found, 5% of falls.

• Stony-Iron - Very rare, 1% of falls.

Differentiated Meteorite

Part of a massive parent body, having been exposed to heal of burial in a parent body and having experienced differentiation (iron meteorite core material).

Primitive Meteorite

A stone that is rich in primordial, simple compounds including water which were in the Solar Nebula. Chondrules are present in the stone.

Widmanstatten Pattern

A large crystal pattern of metals in an iron meteorite. The large crystals are a result of very slow cooling in the parent body.

Chondrules

Spherical grains rich in glassy rock. Indicates very fast cooling, only hours.

Annual Meteor Showers

The Earth is passing through the orbit of a comet, sweeping up dust. The constellation radiant gives the shower its name

• Orionids, Taurus,... etc. 

What do widmanstätten patterns indicate about the history of iron meteorites?

Widmanstatten patterns indicate that over millions of years, the molten metal cooled slowly and is found in the cooling interiors of planetesimal sized objects.

What do chondrules tell you about the history of chondrites?

Chondrules temperatures don’t reach a high enough temperature to melt them. 

Meteorites were once part of which type of celestial object?

Meteorites were once part of Asteroids.

A fragment from the surface of a differentiated asteroid will yield which kind of meteorite?

A fragment from the surface of a differentiated asteroid will yield an Achondrite.